<p>It is just a mining spanning tree ( 最小生成树 ) problem, what makes you a little difficult is that you are in a 3D space.</p>

<div>You are to write a program that draws a border around a closed path into a bitmap, as displayed in the</div> <div>following figure:</div> <div><img width="303" height="306" alt="" src="/admin/../upload/pimg1013_1.png" />…

<img src="http://10.10.44.44:80/admin/../Image/1009/1.jpg" align=right> 1945年初，苏军和英美联军已从东西两面攻入德国国境。 4月初，在苏军和英美联军的夹击下，德军只能龟缩在以柏林为中心的德国东部的狭长地带，成了瓮中之鳖。 但希特勒困兽犹斗，一方面发出摧毁一切设施，实行“焦土”政策的指令； 另一方面下令把德国分为南北两个行政区，各自作战，他自己则固守柏林。 在这一天，苏军结果一份传自柏林的加密电文。经初步破译，显示希特勒要调集10…

<p>There is a famous railway station in PopPush City. Country there is incredibly hilly. The station was built in last century. Unfortunately, funds were extremely limited that time. It was possible to establish only a surface track. Moreover, it turned …

<pre> 在大学里，很多单词都是一词多义，偶尔在文章里还要用引申义。这困扰Redraiment很长的时间。 他开始搜集那些单词的所有意义。他发现了一些规律，例如 “a”能用“e”来代替, “c”能用“f”来代替…… 现在他给出了字母的替换规则，如下所示，A被E替换，B被C替换，依次类推。 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z E C F A J K L B D G H I V W Z Y M N O P Q R S T U X a b …

<p>Redraiment小时候走路喜欢蹦蹦跳跳，他最喜欢在楼梯上跳来跳去。 但年幼的他一次只能走上一阶或者一下子蹦上两阶。 现在一共有N阶台阶，请你计算一下Redraiment从第0阶到第N阶共有几种走法。</p>